bug#16387: 24.3.50; unquittable infloop

[Richard Stallman <rms@gnu.org>]

M-x grep put me in a loop I could not quit out of.
Here's the backtrace after C-g C-g put me into GDB.
Grep had already terminated, but Emacs had not exited the loop
even a minute later.

It happened twice today.  One time, the current buffer was in Mail mode,
and maybe that was true both times.


#0  0x76a4d3c4 in kill () from /lib/libc.so.6
#1  0x00657004 in sys_suspend () at sysdep.c:450
#2  0x0063fcf8 in handle_interrupt (in_signal_handler=true) at keyboard.c:10318
#3  0x0063fb18 in handle_interrupt_signal (sig=2) at keyboard.c:10259
#4  0x006599b0 in deliver_process_signal (sig=2, 
    handler=0x63fa78 <handle_interrupt_signal>) at sysdep.c:1568
#5  0x0063fb74 in deliver_interrupt_signal (sig=2) at keyboard.c:10266
#6  <signal handler called>
#7  0x00000000 in ?? ()
#8  0x00000000 in ?? ()

Lisp Backtrace:
"get-text-property" (0x7fff09e8)
"font-lock-extend-jit-lock-region-after-change" (0x7fff0dbc)
"run-hook-with-args" (0x7fff0db8)
"jit-lock-after-change" (0x7fff1144)
"replace-match" (0x7fff1348)
"grep-filter" (0x7fff1698)
"run-hooks" (0x7fff1710)
"compilation-filter" (0x7fff19dc)




In GNU Emacs 24.3.50.18 (mips64el-unknown-linux-gnu, GTK+ Version 2.20.1)
 of 2013-12-14 on chiefs-gnewsense
Bzr revision: 115526 tzz@lifelogs.com-20131214180409-n2o5017gxsjvz8as
System Description:	gNewSense GNU/Linux 3.0 (parkes)

Configured using:
 `configure 'CFLAGS=-g -O0''

Important settings:
  value of $LANG: en_US.UTF-8
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t

Major mode: RMAIL

Minor modes in effect:
  gpm-mouse-mode: t
  tooltip-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  buffer-read-only: t
  line-number-mode: t
  transient-mark-mode: t
  abbrev-mode: t

Recent input:
ESC x r e p o r t SPC e m a v s DEL DEL c s RET

Recent messages:
Source file `/home/rms/emacs-bzr/trunk/lisp/gnus/mml-sec.el' newer than byte-compiled file
Source file `/home/rms/emacs-bzr/trunk/lisp/emacs-lisp/easymenu.el' newer than byte-compiled file
Source file `/home/rms/emacs-bzr/trunk/lisp/mail/rfc822.el' newer than byte-compiled file
Source file `/home/rms/emacs-bzr/trunk/lisp/format-spec.el' newer than byte-compiled file
Source file `/home/rms/emacs-bzr/trunk/lisp/mail/sendmail.el' newer than byte-compiled file
Counting messages...done
(No new mail has arrived)
0 new messages read
Source file `/home/rms/emacs-bzr/trunk/lisp/gnus/qp.el' newer than byte-compiled file
Source file `/home/rms/emacs-bzr/trunk/lisp/mail/emacsbug.el' newer than byte-compiled file

Load-path shadows:
/home/rms/emacs-bzr/trunk/lisp/leim/quail/lao hides /home/rms/emacs-bzr/trunk/lisp/language/lao
/home/rms/emacs-bzr/trunk/lisp/leim/quail/georgian hides /home/rms/emacs-bzr/trunk/lisp/language/georgian
/home/rms/emacs-bzr/trunk/lisp/leim/quail/thai hides /home/rms/emacs-bzr/trunk/lisp/language/thai
/home/rms/emacs-bzr/trunk/lisp/leim/quail/ethiopic hides /home/rms/emacs-bzr/trunk/lisp/language/ethiopic
/home/rms/emacs-bzr/trunk/lisp/leim/quail/japanese hides /home/rms/emacs-bzr/trunk/lisp/language/japanese
/home/rms/emacs-bzr/trunk/lisp/leim/quail/cyrillic hides /home/rms/emacs-bzr/trunk/lisp/language/cyrillic
/home/rms/emacs-bzr/trunk/lisp/leim/quail/indian hides /home/rms/emacs-bzr/trunk/lisp/language/indian
/home/rms/emacs-bzr/trunk/lisp/leim/quail/hebrew hides /home/rms/emacs-bzr/trunk/lisp/language/hebrew
/home/rms/emacs-bzr/trunk/lisp/leim/quail/greek hides /home/rms/emacs-bzr/trunk/lisp/language/greek
/home/rms/emacs-bzr/trunk/lisp/leim/quail/czech hides /home/rms/emacs-bzr/trunk/lisp/language/czech
/home/rms/emacs-bzr/trunk/lisp/leim/quail/slovak hides /home/rms/emacs-bzr/trunk/lisp/language/slovak
/home/rms/emacs-bzr/trunk/lisp/leim/quail/tibetan hides /home/rms/emacs-bzr/trunk/lisp/language/tibetan

Features:
(shadow mailalias emacsbug qp rmailmm message sendmail format-spec
rfc822 mml easymenu mml-sec mm-decode mm-bodies mm-encode mailabbrev
gmm-utils mailheader mail-parse rfc2231 dired t-mouse package
rmailedit rmail rfc2047 rfc2045 ietf-drums mm-util mail-prsvr
mail-utils time-date paren cus-start cus-load advice help-fns tooltip
electric uniquify ediff-hook vc-hooks lisp-float-type mwheel x-win
x-dnd tool-bar dnd fontset image regexp-opt fringe tabulated-list
newcomment lisp-mode prog-mode register page menu-bar rfn-eshadow
timer select scroll-bar mouse jit-lock font-lock syntax facemenu
font-core frame cham georgian utf-8-lang misc-lang vietnamese tibetan
thai tai-viet lao korean japanese hebrew greek romanian slovak czech
european ethiopic indian cyrillic chinese case-table epa-hook
jka-cmpr-hook help simple abbrev minibuffer nadvice loaddefs button
faces cus-face macroexp files text-properties overlay sha1 md5 base64
format env code-pages mule custom widget hashtable-print-readable
backquote make-network-process dbusbind gfilenotify dynamic-setting
system-font-setting font-render-setting move-toolbar gtk x-toolkit x
multi-tty emacs)
[[[ To any NSA and FBI agents reading my email: please consider    ]]]
[[[ whether defending the US Constitution against all enemies,     ]]]
[[[ foreign or domestic, requires you to follow Snowden's example. ]]]


-- 
Dr Richard Stallman
President, Free Software Foundation
51 Franklin St
Boston MA 02110
USA
www.fsf.org  www.gnu.org
Skype: No way! That's nonfree (freedom-denying) software.
  Use Ekiga or an ordinary phone call.